The present invention relates to a twelve to twenty-four hour unit dosage form comprising an antihistamine and a decongestant. The unit dosage form is useful in treating patients with colds, the flu and other upper respiratory diseases.
Antihistamines include piperidinoalkanol derivatives which are disclosed in U.S. Pat. No. 4,996,061 and incorporated herein by reference. Piperidinoalkanol compounds are useful as antihistamines, antiallergy agents and bronchodialators. Loratadine is a specific type of piperidinoalkanol and is disclosed in U.S. Pat. No. 4,282,233 as an antihistamine with little or no sedative effect. Another preferred antihistamine is the active metabolite of loratadine, descarboethoxy loratadine, which is described in U.S. Pat. No. 4,659,716.
Antihistamines are often administered in combination with sympathomimetic or decongestant drugs. Those skilled in the art recognize sympathomimetic drugs such as pseudoephederine, phenylephedrine and phenylpropanolamine as therapeutic agents effective for the relief of nasal congestion.
Some common combinations of antihistamines and sympathomimetics or decongestants are loratadine and pseudoephedrine as sold commercially under the tradenames CLARITIN®-D 12 HOUR and CLARITIN®-D 24 HOUR.
Once and twice daily controlled release formulations containing a combination of loratadine and pseudoephedrine have been described. These formulations can be undesirable for many reasons including deficiencies in safety, effectiveness and ease of manufacture.
In order to encourage high patient compliance the antihistamine dosage unit should be prepared in a unit dosage form that is taken once or twice daily. These formulations should be stable, economical and easy to manufacture.
It is therefore an objective of the present invention to provide a safe and effective twelve to twenty-four hour antihistamine and decongestant formulation.